Re: A82: ld hl,$FC00+13+(16*7) ---??what??
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Re: A82: ld hl,$FC00+13+(16*7) ---??what??
-----Original Message-----
From: ilya winham <ilyamojo@geocities.com>
To: assembly-82@lists.ticalc.org <assembly-82@lists.ticalc.org>
Date: 14. oktober 1997 04:14
Subject: Re: A82: ld hl,$FC00+13+(16*7) ---??what??
>Patrick Davidson wrote:
>>
>> >What are the screen coordinates of | ld hl,$FC00+13+(16*7) |
>> >At least I think that is what it is used for. It is from an 86
>> >assembly program, used for displaying a small pic.
>>
>> Row 7, column 104
>>
>> The TI-86 screen is a 16 bytes wide bitmap, so the Y coordinate
>> given by the upper 6 bits of the address (7 in this case), and
>> the X coordinate is 8 times the value of the lower 4 bits (13).
>>
>
>So, for the 82, how would I get it to be Row 7, column 78?
>
$FC00+13+(16*7) = Line 7 Column 13. Or generally
$FC00+X+(16*Y) = Line Y Column X
These values can be used on the TI82, but you have to take the difference in
size into concideration.
Dines